Oil Seed Extraction

In recent years, the process improvement in seed extraction plants is laying great emphasis on energy efficiency, cost effectiveness and improved meal quality to meet domestic as well as global market demand.

Considering all these important factors and with the help of modern techniques in process engineering design, DVC Process Technologists offers Oil Seed Extraction plants up to 1000 MTD

We offer following main sections with state of art equipment and high degree automation:

Seed Preparation

Cleaning : Oilseeds from day bin silos are conveyed to Vibratory Seed Cleaner, magnetic separator and De-stoner for cleaning and then oilseeds are sent to Preparation.

Seed Preparation : The cleaned seed are cracked in the fluted roller mill. The cracked seed normally conditioned for removing moisture which acts as bonding between oil droplets and solid proteins.

Conditioned cracked seeds are conveyed to flaking machine where the cracked beans are converted to flakes. The pressed cakes are treated and converted into granules as per required specification. These granules are prepared in the cake breaking machine which is specially designed for this purpose.

Seed Extraction: The prepared raw material is conveyed to extraction plant by a conveyor to the extractor through an air tight rotary valve of adequate capacity driven by suitable geared motor.

Actual treatment with the solvent is done in extractor ,which works on the principle of continuous counter current extraction. In Extractor, the miscella is formed and the material is de-oiled.

The material is scraped off from the bed and rich miscella from the extractor is pumped to miscella tank.

De-Solventization and Toasting (DT)

The wet meal from the extractor contains about 30 -35% hexane after de-oiling of the oil bearing material. From the discharge hopper the wet de-oiled meal is conveyed to De-solventization and Toasting (DT) located at the Drying and Cooling section by an air-tight chain conveyor.

The Scrubber is provided for hexane recovery. The scrubber is compartmental in construction and is provided with double bottom for the heating and equipped with special nozzles for the live steam injection in the system . The required retention time is provided for de-solventizing and toasting of the meal. The process of toasting is ensured by carrying out hydrolyzing the enzymes by cooking with excess moisture and then drying the material to remove the excess moisture.

In each compartment the material holds a preset level which can be varied and adjusted. The open steam is injected into all compartments except bottom which travels upwards and takes out the solvent vapours. The material thus leaving from the DT section is free from the solvent and is also toasted and is free from the enzymes. The solvent vapour and steam form the DT section carries lot of enthalpy and is used to heat the miscella in the distillation section. These vapours carry solid particles which are separated in the vapour cyclone by scrubbing water. The solid separated are sent back into the DT apparatus.

Drying and Cooling ( located at solvent free zone)

Desolventized and toasted meal is dried to have moisture content below 12% by hot air passing into the drying zone. The meal temperature is around 65 0CThe meal is cooled by cold air in cooling section below 45 0C

The levels in bottom compartment in DT section, drying and cooling section are controlled by the specially designed rotary valves which are operated by geared motors. The deoiled meal is conveyed by the mechanical conveyor to meal storage

Miscella distillation section

Miscella from the tank goes to bottom of economizer. The miscella is heated by vapours of DTDC section. The heated miscella from the economizer, achieves the concentration from 20 % to 65 -70 %

The concentrated miscella is conveyed to second evaporator where it is heated by fresh steam and is concentrated to 95 %. The rich miscella of 95% is further conveyed to oil driers which are steam jacketed and operate under vacuum. The traces of solvent are removed by introduced steam.

The recovered crude oil is then conveyed to storage tank.

Hexane Recovery Section

The air space in the Extractor, Hexane water separation tank, Vapour contactor and DT condenser gets saturated with hexane. The incoming meal also carries nearly double the quantity of inflow of the material into the extractor This air gets saturated during travel in the system and has to be discharged into atmosphere after recovering the hexane.

All vapours are taken into the condenser ,where its cooled by cooling water. The vapours are further sub cooled by cooling water at 6 to 8 degC and hexane is recovered.

The air further goes to absorption tower , where mineral oil absorbs hexane. The mineral oil is heated to 90 to 100 degC before it enters the desorption tower. Further, absorbed hexane is desorbed in desorption tower. The mineral oil is kept in circulation and safety filter is provided to remove dirt from the oil.